The documentary “Blackfish” performed swimmingly for CNN, winning the key news demo in its time slot and proving a big draw among younger viewers.

The CNN Films documentary, which chronicles the plight of captive orca whales, averaged 472,000 viewers in the key 25-54 news demo during its 9 to 11 p.m. airing, besting both Fox News Channel and MSNBC in the demo. (FNC and MSNBC averaged 331,000 and 235,000 viewers in the demo, respectively.)